Crane



S. W. RUFF Feb, 18, 1936.

CRANE Filed Feb. 14, 1955 2 sheets-sheet 1 S. W. RUFF Feb. 18,1936

CRANE Filed Feb. 14, 1955 2 Sheets-Sheet 2 567M008 W fiz/FF PatentedFeb. 18, 1936 UNITED STATES PATENT OFF-ICE CRANE Seymour W. Ruff,Baltimore, Md. Application February 14, 1935", Serial No. 6,563

6 Claims.

The invention relates to cranes and more particularly it has referenceto the provision of a crane whose main boom carries an extension boom.

Primarily the invention has for its object to provide a crane which canmake long reaches and lift very heavy loads. Further, it is an object ofthe invention to provide a specially designed crane for the purposes ofraising and setting stone, steel and other building materials on highbuildings and in remote places that cannot be reached in an economicalfashion by any other crane now known; the object is fulfilled by the useof special braces, bridge structures, reinforcements and attachments sothat an auxil iary boom may be attached at a place remote from each endof the main boom.

Further, it is an object of the invention to provide a crane with anextension boom that is mounted on the main boom so as to operate in avertical plane through approximately 150-160 degrees.

A further object is to provide a crane possessing the advantageouscharacteristics above mentioned, with as light a main boom structure asis possible and yet have the structure strong enough to preventbuckling, bending or twisting while a load is being handled.

Other objects will in part be obvious and in part be pointed outhereinafter.

To the attainment of the aforesaid objects and ends the invention stillfurther resides in the novel details of construction, combination andarrangement of parts, all of which will be first fully described in thefollowing detailed description, and then be particularly pointed out inthe appended claims, reference being had to the accompanying drawings,in which:-

Figure 1 is a side elevaiton of the invention, the high and lowpositions of the auxiliary or extension boom being shown in dottedlines.

Figure 2 is an enlarged detail horizontal section on the line 2--2, ofFigure 1.

Figure 3 is an enlarged detail plan view of the lower end of the mainboom.

Figure 4 is an enlarged detail plan view of the upper end of the mainboom.

Figure 5 is a detail plan view of the auxiliary or extension boom.

Figure 6 is a side elevation of the parts shown in Figure 3.

In the drawings, in which like numerals and letters of referenceindicate like parts in all the figures, l represents a tractor of thewellknown Caterpillar type which includes a body comprising a base 3 anda ballast box 2. The construction of the tractor is of a well-known typeand per se is not of the present invention. 8 designates the main boomwhich is composed of a skeleton structure consisting of longitudinalcorner irons 9, zigzag bracing or diagonal bracing bars I0 andtransverse or crossed braces H. The boom is also further braced by lowerreinforcing plates I2, upper reinforcing plates l3 and intermediatereinforcing plates 14 and IS. The main boom is pivoted at 4 to the base3 to swing in a vertical plane. In order to limit the upward movement ofthe main boom to a vertical position it is provided with a bumper, orbumpers, l6 notched at I! to engage a cross bar I which is rigidlymounted on the tractor by means of inverted V-fra'ines consisting offront and rear braces 5 and 6 respectively. 7

Located about two-thirds of the way up the main boom, where theintermediate reinforcing plates 14 are provided, is a bridge member l8that is secured to the boom and projects rearwardly transverselythereof, there being hog rods I9 provided for rigidly connecting thebridge with the respective ends of the main boom. In order that theserods may be placed under tension they are made in sections united byturn-buckles 20. The main boom 8 is swung on its pivot by means of amainboom cable 2| which is anchored at the cross bar or rod 1, passesover a pulley 23 at the free end of the main boom and has its endconnected with the main boom cable drum 22 that is. mounted on the baseof the tractor. At the upper orfree end of the main boom isprovided aguide 24 for the various cables which pass that point.

The extension boom which constitutes an essential part of the presentinvention is indicated at 25 and consists preferably of side bars 26 andspacer blocks 21, there being bearing'plates 28 provided at one end'ofthe'auxiliaryboom to carry the hinge ears through which the hinge pin 30passes, the pin 30 also passing through ears on the hinge members 29that are secured to the main boom in line with the bridge [8 but on theopposite side thereto. The extension boom cable 3| is anchored at 36 tothe extension boom and passes over a series of pulleys 32, 34, 23, 33,and 39 from whence it passes to the extension boom cable drum that ismounted on the base 3.

The load cable is anchored at 40 to the free end of the auxiliary boom,passes around the load hook pulley block 42 and over the pu1leys'38 and39 to the load cable drum 4| which is'also mounted on the base 3.

As shown in Figure 1, when the main boom is in substantially a verticalposition the auxiliary boom may be swung through an arc of approximatelydegrees. In this way it can be used as a longitudinal extension of themain boom, or as a lateral extension of the main boom for the purpose ofreaching over high obstructions to pick up or let down a load beyond theobstruction, making the crane especially adapted to the placing orremoving of a load over a high wall or where the crane cannot be gotteninto the location where the load is to be placed or removed. Bymanipulating both the main and the auxiliary booms an almost unlimitednumber of positions within range of the booms for the load carrying hookto reach can be obtained without the necessity of moving the tractorfrom a given position.

With a crane constructed according to the present invention, should theload cable part or the load break loose while lifting a heavy load, thestructure is such as to resist a flap back and a tendency of the boom todouble up, thereby avoiding a great danger present in cranes used priorto this invention. Experience has shown that with a crane having astandard main boom 2. sixty foot extension boom can readily be used; infact in experiments a seventy-three foot boom has been foundpracticable.

From the foregoing description, taken in connection with theaccompanying drawings it is though that the complete construction,operation and advantages of the invention will be clear to those skilledin the art.

What I claim is:

1. In apparatus of the character described, a base, a main boom hingedlymounted at its lower extremity to said base, a bridge secured to saidmain, boom, hog rods anchored to said bridge and to the respective endsof said main boom, said bridge extending transversely from the main boomrearwardly, an auxiliary boom hingedly mounted on said main boom at thefront thereof and adjacent said bridge, a main boom elevating andlowering cable and a drum therefor carried by said base, an extensionboom lowering and raising cable and a drum therefor carried by saidbase, a load cable carried by said booms and a drum therefor carried bysaid base.

2. In apparatus of the character described, a base, a main boom hingedlymounted at its lower extremity to said base, a bridge secured to saidmain boom and located at approximately twothirds of the length of theboom from the base, hog rods anchored to said bridge and to therespective ends of said main boom, said bridge extending transverselyfrom the main boom rearwardly, an auxiliary boom hingedly mounted onsaid main boom at the front thereof and adjacent said bridge, a mainboom elevating and lowering cable and a drum therefor carried by saidbase, an extension boom lowering and raising cable and a drum thereforcarried by said base, a load cable carried by said booms and a drumtherefor carried by said base.

3. In apparatus of the character described, a base, a main boom hingedlymounted at its lower extremity to said base, a bridge secured to saidmain boom and located at approximately twothirds of the length of theboom from the base, hog rods anchored to said bridge and to therespective ends of said main boom, said bridge extending transverselyfrom the main boom rearwardly, an auxiliary boom hingedly mounted onsaid main boom at the front'thereofand adjacent said bridge, a main boomelevating and lowering cable and a drum therefor carried'by said base,an extension boom lowering and raising cable and a drum therefor carriedby said base, a load cable carried by said booms, a drum thereforcarried by said base, and means to place said hog rods under tension.

4. In cranes, a base having a counterbalance box, a main boom cabledrum, an extension boom cable drum and a load cable drum, said drumsbeing carried by said base, a main boom pivoted on a horizontal axis tosaid base, a main boom cable connected to the free end of said main boomand with said main boom cable drum, said main boom comprising a skeletonsteel structure consisting of corner longitudinals reinforced byvertical zigzag braces and transverse crossed braces, reinforcing platesadjacent the ends of said main boom and at intervals in its length, abridge secured to said main boom intermediate its ends and projectingtransversely to the rear thereof, an auxiliary boom pivoted to said mainboom in front thereof and adjacent said bridge, hog rods connecting saidbridge with the ends of said main boom, an auxiliary boom cable one endof which is anchored to said auxiliary boom and the other end of whichis connected to said auxiliary boom cable drum, pulleys on said boomsaround which said auxiliary boom cable is passed, a work cable one endof which is anchored to said auxiliary boom and the other end of whichis connected with said work cable drum, and pulleys on said booms overwhich said work cable is passed. I

5. In cranes, a base having a counterbalance box, a main boom cabledrum, an extension boom cable drum and a load cable drum, said drums 5being carried by said base, a main boom pivoted on a horizontal axis tosaid base, a main boom cable connected to the free end of said main boomand with said main boom cable drum, said main boom comprising a skeletonsteel structure consisting of corner longitudinals reinforced byvertical zigzag braces and transverse crossed braces, reinforcing platesadjacent the ends of said main boom and atintervals in its length, abridge secured to said main boom intermediate its ends and projectingtransversely to the rear thereof, an auxiliary boom pivoted to said mainboom in front thereof and adjacent said bridge, hog rods connecting saidbridge with the ends of said main boom, an auxiliary boom cable one endof which is'anchored to said auxiliary boom and the other end of whichis connected to said auxiliary boom cable drum, pulleys on said boomsaround which said auxiliary boom cable is passed, a work cable one endof which is anchored to said auxiliary boom and the other end of whichis connected with said work cable drum, pulleys on said booms over whichsaid work cable is passed, and a guide on the end of said main boom forsaid cables.

6. In cranes, a body, a main boom pivotally mounted on said body formovement in a vertical plane, a bridge projecting transversely from saidmain boom and located intermediate the ends thereof, hog rods connectingsaid bridge with the respective ends of said main boom, an auxiliaryboom pivoted to said main boom adjacent said bridge and projectingoppositely thereto, main and auxiliary boom cables and drums foroperating said booms, and a work cable and drum cooperating with saidbooms, said auxiliary boom being movable in a vertical plane through anarc of approximately 160 degrees. SEYMOUR W. RUFF.

